"In a way, you could say that the modern magus is in the business of gathering angels."

The detached castle Adra.
Like a lone living being, it is a demon castle created by magi who were fascinated with angels.
The ruler (Lord) of modern thaumaturgy at the Clock Tower, El-Melloi II, gets caught up in a battle for succession over the detached castle. The interior of the castle is adorned with many angels.
Only those who have unraveled the mysteries of the Angel Names granted them are invited to inherit the detached castle.
However, it was no simple solution to a riddle. To the high-ranking magi of the Clock Tower, it was the beginning of an excessively fantastic tragedy--.

Now, the curtain rises on the "Lord El-Melloi II Case Files", which blends riddles and illusions, thaumaturgy and mysteries.

Mystic Eyes Collection Train. A legend that even now keeps running in the forest of Europe.
Due to being dragged into by a certain invitation letter, it has been decided that Lord El-Melloi II would participate in an auction of mystic eyes together with Olga Marie and others from the Astronomy Department's (Animusphere) family. However, El-Melloi II's objective lies not in the auction. But to recover his indispensable--- stolen pride.
Those who desire mystic eyes, and those who shun mystic eyes.
What is the mystic eyes of "Rainbow" rank, regarded as a top secret?

The October issue of Kadokawa's Young Ace magazine revealed the Novel will receive a manga adaptation illustrated by Toh Azuma. It debuted in the magazine's November issue on October 4.[2] Published by Kadokawa Shoten, the first volume of the manga was released on July 3, 2018. The second volume is released on August 4, 2018 and the third on January 10, 2019.

After Type-Moon teased a new animation project, produced by studio Troyca, a TV anime special episode "Episode 0" for the series was set to air December 31, 2018, during the Fate Project Ōmisoka TV Special 2018. Handled by Troyca, a full anime TV Series named Lord El-Melloi II Case Files -Mystic Eyes collection trainRail Zeppelin Grace note- (ロード・エルメロイⅡ世の事件簿 -魔眼蒐集列車レール・ツェッペリン Grace note-, Rōdo Erumeroi Ⅱ Yo no Jikenbo -Magan shūshū resshaRēru Tsepperin Grace note-?) was then announced to start airing July 6, 2019.[3] It will adapt the "Rail Zeppelin" case of the Light Novel, while including anime original content.[4]